I was 21 at the time my symptoms started, 9 months ago in August. There was no trigger as far as I can tell. I just came home from work one evening, rested on my bed, and suddenly felt my heart rate accelerate to 120BPM, where it stayed for the next 6 hours, along with symptoms of anxiety and impending doom. The next morning my heart rate was 90BPM, and the symptoms abated for about a week, until they repeated themselves again. I would suffer from dissociative symptoms, anxiety and bodily pain for the next four months. It was only in February that I realised I had orthostatic tachycardia. Since January my symptoms have been decreasing in frequency and intensity, albeit slowly. I was found to be vitamin D deficient in March, but that has since been corrected.